There hasn’t been so much optimism surrounding the Philadelphia Eagles as a new season is about to kick off in exactly one decade.

In 2004, the Birds were coming off of their third consecutive appearance in the conference title game and had acquired six-time Pro Bowl wide receiver Terrell Owens to help get the franchise over the hump and into the Super Bowl.

This time, the Eagles are following a 10-6 record with an NFC East title and first-round playoff exit, and it’s not a player who has galvanized a fanbase or preseason prognosticators.

All of the enthusiasm and excitement can be traced to the Chip Kelly effect, as he looks to build on a successful first season as an NFL head coach.

Sure, some observers harbor reservations about the Eagles as a legitimate contender in 2014. There are doubts at quarterback, at wide receiver and all over the defense.

That being said, there is a strong sense that Kelly has the Eagles headed in the right direction, and in some cases, that anything is possible with Chip.

No matter how great a coach is, though, the game of football still boils down to the ability of the players on the field. The question isn’t whether Kelly can lead Philadelphia to the promised land—it’s can he do it with the roster he’s assembled?

With that in mind, we’re going in depth with all 53 members of the Eagles, examining how these moving parts fit together, who the potential X-factors could be for a possible Super Bowl run and which games on the regular-season schedule will be the proving grounds for this squad.

Has Kelly done the unthinkable and built a championship contender in two short years?

Quarterback

All eyes are on Foles as the 25-year-old signal-caller attempts to follow a historic campaign. Duplicating aspects of his 2013 numbers falls somewhere between unlikely (119.2 passer rating) and short of impossible (29 touchdowns to 2 interceptions, including playoffs).

But if the third-year quarterback can guide Philadelphia to a second consecutive division title, few people will mind.

In Sanchez, the Eagles appear to have one of the best backups in the league. Completing 25 of 31 passes (80.6 percent) during the preseason could have been a mirage, considering the sixth-year veteran is a career 55 percent passer.

However, you can’t really argue with a 37-31 record in 68 career starts, including a 4-2 mark in the playoffs.

Barkley never appeared to be in the running for the No. 2 job, but last year’s fourth-round pick is signed through 2016.

He made strides in his second training camp, completing 63.1 percent of his pass attempts during the preseason compared to 50.8 fresh out of USC.

Running Back

For my money, there isn’t a more complete back in the NFL today than McCoy. Obviously, the league’s reigning rushing champion can dominate on the ground, but the two-time All-Pro is also second to none as a receiver out of the backfield or in pass protection.

At just 26 years old, McCoy is only 1,065 yards away from becoming the Eagles’ all-time leading rusher.

Initially, I was skeptical as to how much Sproles had left in the tank, but after seeing him up close and personal at training camp, I believe he could play a larger role in the offense than some of the most optimistic projections.

It seems nagging injuries, not age, may have been to blame for the decline in numbers with the New Orleans Saints in 2013, which in terms of yards per carry (4.2), yards per reception (8.5), punt return average (6.7) and total touchdowns (4) was probably Sproles’ worst season since his rise to prominence.

From what I’ve been able to glean, Sproles looks like his old self—and the Eagles plan to use plenty of two-back formations.

Polk’s spot appeared to be in jeopardy due to a hamstring injury that prevented him from practicing or playing most of the summer. However, Adam Caplan for ESPN reports the third-year back is expected to be ready for Week 1.

Last season, Polk became the first running back in NFL history to rush for three touchdowns on only 11 carries.

Wide Receiver

For the first time since his 19th overall selection in the 2009 draft, Maclin is unrivaled as the feature receiver in Philadelphia’s offense. The concern there is the surgically repaired ACL that erased his ’13 campaign.

It should be interesting to track Cooper’s progress this season. After an outlandish five-game stretch that exaggerated his numbers, the longtime backup averaged 3.6 receptions for 49.7 yards per game with two touchdowns over the final seven contests last season, including playoffs.

As mediocre as that sounds, the figures work out to 57 catches, 795 yards and five touchdowns over a full season—not terribly far off from Cooper’s line in 2013.

Maehl is back for a second season with the Eagles after appearing on just 129 offensive snaps in 2013, according to game charters at Pro Football Focus (subscription required).

The fourth-year veteran might be the first man off the bench in the event either Maclin or Cooper is unavailable.

There is some question as to who will serve as the primary slot receiver, at least initially. Smith ran with the first-team offense during training camp. The ninth-year veteran surely will have some role to play, but his roster spot was reserved as much for special teams prowess as offensive ability.

Smith is expected to give way to Matthews eventually, if not from Day 1. The Eagles traded up 12 picks to No. 42 overall to snatch the wide receiver out of Vanderbilt, to much fanfare.

Matthews looks like the total package—size, speed, strength, production, intelligence, work ethic. The 22-year-old was the clubhouse leader with 15 catches and 134 yards during the preseason.

Huff was taken one round later, but he is not expected to contribute much to the offense as a rookie.

Tight End

Celek has transformed himself into one of the best blocking tight ends in the NFL, which is how the eighth-year veteran maintains his spot at the top of Philadelphia’s depth chart.

He’s still a fine receiver, too. Celek's 15.7 yards per reception in 2013 were three full yards better than his career average, while six touchdowns were the second-highest total of his career.

As good as Celek is, he won’t be able to hold off Ertz forever. A second-round pick in 2013, the Stanford product appears poised for a breakout season after a strong finish to his rookie campaign.

He recorded five touchdown passes over the Eagles’ final six games, including playoffs. Expect the offense to increase its use of two-tight end sets to accommodate for more Ertz.

Hailed as one of the club’s prized free-agent signings last offseason, Casey has been the clear No. 3 behind Celek and Ertz all along. Casey is back for another year, largely for his special teams contributions, although he isn’t a bad backup, either.

Burton was something of a surprise choice for the roster. An undrafted rookie, Burton is both undersized (6’3”, 235 lbs) and raw.

However, he’s incredibly versatile, having lined up at tight end, wide receiver, running back and even quarterback at Florida—not to mention he plays special teams.

Six receptions for 45 yards with a 21-yard touchdown in the final preseason game likely sealed Burton’s spot. He figures to render Casey expendable in 2015.

Offensive Line

How amazing is Peters’ comeback from a twice-ruptured Achilles tendon? The 10th-year veteran returned from one of the most devastating injuries in sports almost as if he never missed a beat, earning his sixth Pro Bowl nod at left tackle.

Peters is 32 now, so some drop-off in performance is to be expected, but he’s still one of the best in the business.

Mathis was finally recognized as the best left guard in the NFL in 2013, earning first-team All-Pro honors for the first time. He’s been one of the league’s most consistent technicians for three years running.

That being said, Mathis is 32 as well, so the Eagles’ dominant left side could be headed for decline sooner or later.

At least the offensive line is young at the heart. In three short years, Kelce has developed into one of the top young centers in the NFL, receiving the highest cumulative score at his position from metrics site Pro Football Focus’ grading system (subscription required).

A 2011 sixth-round pick, Kelce agreed to a long-term contract extension during the offseason.

To Kelce’s right is more of the old guard—quite literally. The longest-tenured player on the Eagles, Herremans is still serviceable at 31 years of age. He looked far more comfortable being back at guard in 2013 after a two-year experiment at right tackle.

Barbre was promoted to starter at right tackle at the onset of training camp amid news Lane Johnson is suspended for four games.

Barbre performed well in relief appearances for the Eagles last season, but there’s a reason the 30-year-old journeyman wasn’t able to stick to a roster before he landed in Philly.

The countdown to Johnson’s return to the lineup will be on as soon as the 2013 fourth overall draft pick is eligible to return—if not beforehand.

Of the reserves, Tobin could be first off the bench at multiple spots. Tobin signed on to play tackle last year as an undrafted free agent out of Iowa, but he has been learning to play left guard.

Left guard is where his preseason performance received PFF’s highest cumulative grade of any NFL lineman this summer. He may be an option at both positions, on either side.

One job that would not fall to Tobin is at center, where Molk has cemented the backup role. Signed to a futures contract in January, the 2012 seventh-round pick of the San Diego Chargers posted the best cumulative score at his position this preseason, based on PFF’s system.

Philadelphia is Gardner’s fifth team in six NFL seasons, but he played well at left tackle this summer. A 2012 fifth-round pick at tackle, Kelly looks strictly like a backup right guard.

The next four weeks could be an extended tryout between the two, as the club will need to free up a roster spot once Johnson returns.

Defensive End

The Eagles are hoping added depth at defensive end alleviates some of the pressure on Cox, who seemed to wear down late last season.

Otherwise, the 12th overall pick of the 2012 draft acquitted himself nicely for his first season in a 3-4 defense, leading the club with 21 hurries. Cox is a strong candidate to improve on 3.0 sacks.

He should get some relief from Bair, who wound up making the team largely on the strength of a disruptive preseason. The 29-year-old will see his first-ever regular-season action after registering eight tackles this summer, which tied for the most among Philly’s defensive linemen.

Thornton emerged from out of nowhere in 2013 to become one of the league’s premier run defenders, but he offers next to nothing in the way of a pass rush. For that reason, his spot at left defensive end is likely subject to operate on more of a platoon basis this season.

Expect Curry to sub in for Thornton with greater frequency, particularly on obvious passing downs. The shift was already underway late last season, as the coaches were running out of excuses to keep the 2012 second-round pick off the field.

Curry finished 2013 with four sacks and 11 hurries—both good for third on the team despite limited playing time, including a pair of healthy scratches. He may not be a perfect fit for the 3-4, but Curry’s explosive first step is almost uncanny.

Hart had a quiet preseason, but the Eagles have a fifth-round pick invested, and he knows the scheme. He’ll mostly eat snaps this year barring unlikely sudden and rapid development.

Nose Tackle

Logan isn’t the blimp-sized human being people tend to imagine when they think of a nose tackle in a traditional 3-4 defense, but the third-round pick out of LSU held his own as a rookie in 2013.

He bulked up to 315 pounds during the offseason, though he has been slowed by a hamstring injury this summer, making it hard to get a read on his progress.

Meanwhile, the coaching staff has to be absolutely thrilled with Allen, who is proving to be quite a find in the seventh round of this year's draft. Allen made the most of the opportunities created by Logan’s absence, so much so that the rookie could push for the starting job.

At 333 pounds, Allen is already the heaviest defensive lineman on the team, so based on the stereotype at least, he’s ready to take over.

Outside Linebacker

This could be Cole’s final season in midnight green, as the ninth-year veteran’s cap figure is set to balloon to north of $11 million in 2015, according to Spotrac.

The Eagles are hoping the 31-year-old has one good season left, as the two-time Pro Bowler is their only proven every-down pass-rusher. All nine of Cole’s sacks last season came in the final nine weeks, including playoffs.

Cole is backed up at the predator position by Graham, whom the Eagles just can’t quit. Timing has never been Graham’s thing, as injuries, free-agent acquisitions and scheme changes have conspired to hold the 2010 first-round pick down the depth chart.

If he ever got a shot at significant playing time, Graham could approach double-digit sacks.

Barwin is the starter on the opposite side, or jack, as it’s commonly referred to in Philadelphia’s defense. It’s a fitting title, as Barwin is a jack of all trades, master of none. Signed to a free-agent contract last offseason, it’s that versatility that allows the Eagles’ 3-4 defense to work.

With Cole and Barwin around, Smith was never expected to start on opening day despite the lofty expectations normally tied to a first-round pick. That’s actually a good thing, because he looked like a project this summer.

Smith flashed some potential in run support and in coverage, but it could be a while until he learns how to rush the passer at the NFL level—the very skill many thought he was drafted to provide.

A free agent from the Houston Texans, Braman was signed almost exclusively as a special teams ace. The fourth-year veteran was an alternate at the Pro Bowl in 2012.

Interior Linebacker

Ryans is a little out of his element as an every-down linebacker in a 3-4, but he gets by on veteran savvy and doing the little things right—namely sure tackling and knowing his assignment.

Despite the issues with fit, the two-time Pro Bowler set career highs with four sacks and two interceptions in 2013.

The 30-year-old can be a bit of a liability in coverage, so he’s unlikely to lead all NFL defenders in snaps played for a second consecutive season, but Ryans remains the unquestioned leader of Philadelphia’s defense.

Then again, it might not be long until Ryans is passing the torch to Kendricks. The third-year interior linebacker finished 2013 on a high note.

In the final eight games he started and completed—including playoffs—Kendricks racked up 67 tackles, all four of his sacks for the season, three pass breakups, two interceptions and two forced fumbles.

If training camp and preseason serve as any indication, that might be par for the course for the soon-to-be 24-year-old going forward.

Goode is the primary backup at either interior spot. He held his own in place of Kendricks in two relief appearances last season, registering three pass breakups and a sack.

A fifth-round pick by the Tampa Bay Buccaneers in 2012, Goode might spell Ryans occasionally, but he is more likely pegged for a break-glass-in-case-of-emergency role.

Matthews defied the odds to make the roster again, largely due to an unfortunate season-ending injury to Travis Long, it would seem. The 2011 fourth-round pick is viable on special teams but doesn’t make for a very good linebacker.

Cornerback

Like Trent Cole, Williams could be a cap casualty in 2015, but for now, he’s the best the Eagles have on the outside. To his credit, Williams kept big plays to a minimum last season, although often at the expense of concessions underneath.

That being said, the former Baltimore Raven has done exactly what he was signed to do, bringing stability and leadership to the secondary.

As it turns out, it may not be Fletcher starting opposite Williams at cornerback. Carroll was one of the standouts at training camp this summer, so much so that he could sneak into a full-time role.

Signed to a two-year deal during free agency, Carroll started 22 games over the past two seasons for the Miami Dolphins, so it’s not a stretch. If nothing else, Carroll is expected to see plenty of action in the brand-new dime package reported by Geoff Mosher for CSNPhilly.com.

As for Fletcher, he remains the starter for now as far as we know, and he is coming off a decent season, finishing tied for 22nd in the NFL with 17 pass breakups. The former St. Louis Ram heads back to the free-agent market at season’s end.

The star of the show is a guy who was only on the field roughly half the time in 2013. Despite being limited to his role as a slot specialist, Boykin somehow managed to finish tied for second in the NFL with six interceptions.

Those picks had a profound effect on Philadelphia’s chances of winning, as all six came in victories. Four were in the fourth quarter.

Watkins was selected in the fourth round of the draft. The Eagles will hope to hide him on the bench until he gets acclimated to the NFL.

Safety

USA TODAY Sports

Malcolm Jenkins, Nate Allen, Earl Wolff, Chris Maragos

The Eagles wasted little time signing Jenkins, swooping in less than an hour after free agency opened in March. There were bigger names on the market, but the exiled New Orleans Saint was viewed as the best fit.

Yes, Jenkins was younger (26) and cheaper—three years, $16.5 million, $8.5 million guaranteed, according to Spotrac—than some of the others. However, he’s also comfortable playing man coverage, and he is a leader on and off the field.

Re-signed to a one-year deal during the offseason, Allen beat out Wolff for the starting job opposite Jenkins in a battle that never got very heated. The fifth-year safety improved gradually as last season went on, to the point where his performance rated somewhere between adequate and good.

Impact plays were lacking (1 SK, 1 INT, 1 FF), but this will be the first time Allen has served under the same defensive coordinator two seasons in a row since the Eagles selected him in the second round in 2010.

Wolff will remain in the mix, but the 2013 fifth-round pick looks like a competent backup for now. Despite being snubbed for a starting gig, he forced two fumbles and registered a pass breakup during the preseason.

Maragos was signed as a free agent largely to upgrade special teams play. He arrives in Philadelphia having just won the Super Bowl as a member of the Seattle Seahawks, although Maragos does not have much of a pedigree on defense.

Specialists

The good news is Alex Henery is gone. That being said, the Eagles are not necessarily settled at kicker.

Parkey was 4-of-4 on field-goal attempts during the preseason, including from 53 and 54 yards—both longer than Henery’s career best—but that’s a small sample size.

At least Parkey appears to have a bigger leg, anyway, but the undrafted rookie out of Auburn remains an unknown.

Jones signed a long-term extension during the offseason after a stellar year as Philadelphia’s punter. The 11th-year veteran set a franchise record with 33 punts down inside the opponents’ 20-yard line, undoubtedly helping the Eagles win some games in the process.

During one memorable two-game stretch, Jones pinned 11 of 14 attempts inside the 20, including kicks of 69 and 70 yards, paving the way for a pair of NFC Special Teams Player of the Week awards.

Dorenbos has been Philadelphia’s long snapper since taking over for Mike Bartrum in 2006. I can’t recall a botched snap in all of the years since.

X-Factors

Philadelphia’s offense is a likely top-five unit again, and it will undoubtedly finish inside the top 10.

However, the unit could prove nearly unstoppable if Maclin finally lives up to his full potential this season—or even comes close to DeSean Jackson’s 2013 numbers.

It certainly isn't out of the question. Just about every offensive skill player enjoyed a career year of sorts in Chip Kelly’s first season on the sidelines, so why would Maclin not experience the same bump in production? That would mean improving on his 2010 line of 70 receptions, 964 yards and 10 touchdowns.

Jackson set personal bests in ‘13 with 82 receptions for 1,332 yards, and he matched another with nine touchdowns. His previous highs were 62, 1,156 and nine in ’09.

Of course, the elephant in the room is the torn ACL that knocked Maclin out last year, the obvious concerns being he’s not completely recovered or is prone to more injuries.

Health will be important for Maclin, especially considering the uncertain depth at wide receiver.

Assuming Maclin does manage to stay out of the infirmary, I see him exceeding expectations—perhaps even to the tune of his first Pro Bowl invite.

With the additions of Sproles and Matthews, and the continued growth of Ertz, if Maclin can pull off somewhere in the neighborhood of 1,200 yards with eight to 10 touchdowns, Philly’s offense can be flat-out scary.

Defense: Malcolm Jenkins

The only major upgrade to the defense came in the form of Jenkins at safety, so it stands to reason the unit’s rise or fall is tied to how he performs.

Sure, young players such as Cox, Kendricks and Boykin could take the proverbial next step in 2013, but that’s liable to be offset to a degree by the decline of veterans like Cole, Ryans and Williams.

Jenkins’ time in New Orleans has been met with mixed reviews. On one hand, he was a starter for the Super Bowl champion Saints as a rookie in 2009 and just last season played a role in the league’s No. 2 pass defense.

Then again, he’s never been much of a playmaker, one reason the Saints went with Jairus Byrd in the offseason.

Jenkins has just 4.5 sacks, six interceptions and six forced fumbles in five seasons. There have also been battles with durability—Jenkins has never started 16 games—nor is he the surest tackler.

Still, the Eagles stand to be greatly improved with Jenkins. Patrick Chung was nothing short of abysmal in that spot last season. There’s no way his replacement could do worse.

Plus, there’s reason to believe Jenkins might benefit from the change of scenery. The Eagles utilize their safeties in quite a bit of man coverage, something the converted cornerback out of Ohio State is very comfortable doing.

Perhaps a scheme that is suited, if not designed, to his strengths will bring out the best in Jenkins.

That part remains to be seen, but there’s no question the guy can play, which is a lot more than what can be said of his predecessor.

If Jenkins can acclimate to a new defense, he can be more than just another stopgap in Philadelphia’s secondary. Who knows, maybe he could finally live up to that first-round pick the Saints spent.

Special Teams: Cody Parkey

Let’s face it: Parkey is on a short leash. The Eagles will be scouring the waiver wire for a new kicker in a hurry if this kid misses so much as a field-goal try or two.

That being said, the rookie has an opportunity to turn a glaring weakness into an area of strength.

Henery was allowed to attempt all of five field goals from 50 yards by two separate Eagles coaching staffs in three NFL seasons, while Parkey was 2-of-2 from 50 yards in one preseason game. That kind of range is a weapon.

Parkey could help Philadelphia in the game within the game as well—the field-position battle. Henery never finished better than 20th in the NFL in touchback rate, while Parkey led the nation in total touchbacks as a senior at Auburn.

Preventing the opponent from returning a kick is another valuable tool to have.

You might not want to get too excited yet, because Parkey seriously could be gone and forgotten in a month if he doesn’t pan out.

Then again, how could you not feel better about the kicking situation now that the Birds have somebody with an NFL leg?